In my Svelte 3 component library I’m using this Rollup configuration to conditionally render custom elements. Only files with the *.wc.svelte extension are compiled as HTML5 web components.

export default {
  ...
  plugins: [
    /** Handle HTML5 Web Components **/
    sveltekit({
        include: /.wc.svelte$/,
        compilerOptions: {
          // enable run-time checks when not in production
          dev: !production,
          customElement: true,
        },
        // store CSS in JavaScript
        emitCss: false,
      }),
  
      /** Handle Svelte Components **/
      sveltekit({
        exclude: /.wc.svelte$/,
        compilerOptions: {
          // enable run-time checks when not in production
          dev: !production,
          customElement: false,
        },
        // we'll extract any component CSS out into
        // a separate file - better for performance
        emitCss: true,
      }),
  ]

Now I’m migrating to Svelte 4 / SvelteKit.

How can I translate the same behaviour to the Vite configuration?